[Common] Sanitize power-law mapping in corner cases

Author: David Dobrigkeit Chinellato

Common/Tools/Multiplicity/MultModule.h

@@ -505,16 +505,6 @@ class MultModule
       listOfRequestors[kPVMults].Append(Form("%s ", "dependency check"));
     }
 
-    // capture the need for PYTHIA calibration in Pb-Pb runs
-    if (metadataInfo.isMC() && mRunNumber >= 544013 && mRunNumber <= 545367) {
-      internalOpts.generatorName.value = "PYTHIA";
-    }
-
-    // capture the need for PYTHIA calibration in light ion runs automatically
-    if (metadataInfo.isMC() && mRunNumber >= 564250 && mRunNumber <= 564472) {
-      internalOpts.generatorName.value = "PYTHIA";
-    }
-
     // list enabled tables
     for (int i = 0; i < nTablesConst; i++) {
       // printout to be improved in the future
@@ -1145,6 +1135,20 @@ class MultModule
   {
     if (bc.runNumber() != mRunNumberCentrality) {
       mRunNumberCentrality = bc.runNumber(); // mark that this run has been attempted already regardless of outcome
+      LOGF(info, "centrality loading procedure for timestamp=%llu, run number=%d", bc.timestamp(), bc.runNumber());
+
+      // capture the need for PYTHIA calibration in Pb-Pb runs
+      if (metadataInfo.isMC() && mRunNumber >= 544013 && mRunNumber <= 545367) {
+        LOGF(info, "This is MC for Pb-Pb. Setting generatorName automatically to PYTHIA");
+        internalOpts.generatorName.value = "PYTHIA";
+      }
+
+      // capture the need for PYTHIA calibration in light ion runs automatically
+      if (metadataInfo.isMC() && mRunNumber >= 564250 && mRunNumber <= 564472) {
+        LOGF(info, "This is MC for light ion runs. Setting generatorName automatically to PYTHIA");
+        internalOpts.generatorName.value = "PYTHIA";
+      }
+
       LOGF(info, "centrality loading procedure for timestamp=%llu, run number=%d", bc.timestamp(), bc.runNumber());
       TList* callst = nullptr;
       // Check if the ccdb path is a root file
@@ -1258,6 +1262,10 @@ class MultModule
       auto populateTable = [&](auto& table, struct CalibrationInfo& estimator, float multiplicity, bool isInelGt0) {
         const bool assignOutOfRange = internalOpts.embedINELgtZEROselection && !isInelGt0;
         auto scaleMC = [](float x, const float pars[6]) {
+          float core = ((pars[0] + pars[1] * std::pow(x, pars[2])) - pars[3]) / pars[4]; 
+          if(core<0.0f){ 
+            return 0.0f; // this should be marked as low multiplicity and not mapped, core^pars[5] would be NaN
+          }
           return std::pow(((pars[0] + pars[1] * std::pow(x, pars[2])) - pars[3]) / pars[4], 1.0f / pars[5]);
         };
 
@@ -1343,6 +1351,10 @@ class MultModule
       ConfigureCentralityRun2(ccdb, metadataInfo, firstbc);
 
       auto scaleMC = [](float x, const float pars[6]) {
+        float core = ((pars[0] + pars[1] * std::pow(x, pars[2])) - pars[3]) / pars[4]; 
+        if(core<0.0f){ 
+          return 0.0f; // this should be marked as low multiplicity and not mapped, core^pars[5] would be NaN
+        }
         return std::pow(((pars[0] + pars[1] * std::pow(x, pars[2])) - pars[3]) / pars[4], 1.0f / pars[5]);
       };